/**
 * @param {string} type ="Point"|"LineString"|"Circle"|"Polygon"
 * "Square"|"Box"
 *  */
export function createDraw({
    type = "Point",
    source,
    success
}) {
    let geometryFunction = null;
    let maxPoints = null
    if (type == "Box") {
        type = "LineString";
        maxPoints = 2;
        geometryFunction = function (coordinates, geometry) {
            if (!geometry) {
                //多边形
                geometry = new ol.geom.Polygon(null)
            }
            var start = coordinates[0]
            var end = coordinates[1]
            geometry.setCoordinates([
                [start, [start[0], end[1]], end, [end[0], start[1]], start],
            ])
            return geometry
        }
    } else if (
        type == "Square"
    ) {
        type = "Circle";
        geometryFunction = ol.interaction.Draw.createRegularPolygon(4)
    }
    let draw = new ol.interaction.Draw({
        type,
        source,
        geometryFunction,
        maxPoints
    })
    if (typeof success == 'function') {
        /* 打印绘制得到的feature */
        draw.on("drawend", evt => {
            success(evt.feature);
        })
    }
    return draw;
}
